反应详情

Dissolve 3-chloro-5-fluorobenzaldehyde (4.0 g, 25.2 mmol) in glacial acetic acid (15 mL). Add nitromethane (4.1 mL, 75.7 mmol) and ammonium acetate (1.94 g, 25.2 mmol) and heat to reflux for 4 hours. Cool and pour over ice. Dilute with 2 N sodium hydroxide and extract with ethyl acetate, dry (magnesium sulfate), concentrate and purify (silica gel chromatography, eluting with 1:1 dichloromethane:hexanes) to give the desired compound as a beige solid (2.97 g, 58%).

1. temperatureto reflux for 4 hours
2. temperatureCool
3. additionpour over ice
4. extractionextract with ethyl acetate
5. dry with materialdry (magnesium sulfate)
6. concentrationconcentrate
7. custompurify
8. wash(silica gel chromatography, eluting with 1:1 dichloromethane:hexanes)